Device for handling of ropes and use thereof

ABSTRACT

A device is described for handling of a line that is coiled onto a rotary drum, where the line that is coiled is led through a breaking body ( 20 ) that gives a firm and approximately constant tightening in the stretch of the line towards the drum so that the coils of the line around the drum are lying sufficiently tightened. The device is characterised in that the breaking body ( 20 ) comprises breaking units ( 21,22,23 ) that offer resistance against the coiling of the drum ( 11 ) of the line, said breaking body ( 20 ) comprises a number of line guiding discs ( 21,22,23 ) via which the line is set up to be led and form a loop, said disc guide groves ( 36 ) offer said breaking effect against the hawser up to the drum ( 11 ). According to the invention, the device can be used in the handling of hawsers for anchor handling that are loosely coiled onto storage drums from the supplier, with the hawser from the storage drum being transferred into a considerably tightened state by being coiled onto a winch drum with such force that it lies compact and taut on the drum. According to another application, it is used for the tightening of wires, cables, fibrous hawsers, and the like on winch drums in connection with cranes.

The present invention relates to a device for handling of a line that is wound onto a rotating drum, such as a winch drum, where the line which is wound up is led through a breaking body that gives a firm and approximately constant tightening to the stretch of line towards the drum, so that the line coils around the drum are lying sufficiently taut, as can be seen in the introduction of the subsequent claim 1.

More specifically, it is an aim of the invention to be able to tighten a slack hawser, such as a fibrous hawser, so that it can be wound tightly onto a drum.

The solution according to the invention is intended for use on board anchor handling vessels, but can also be used in other applications. At deep waters, synthetic hawsers are often used as anchor lines for floating offshore installations. The manufacturers of hawsers supply the hawsers loosely wound onto storage drums. The hawsers are normally spooled over onto the winches of the vessel at an offshore base.

So that the hawser can be made slack out from the winch on the anchor handling vessel with a load, the hawser must initially be tightly coiled.

As the hawser is coiled loosely on the storage drums, it is initially spooled loosely onto the winches of a ship. This is because the hawser will sink down between the layers on the storage drum if the tension is too great, something which can lead to the hawser becoming damaged. Thereafter, the end of the hawser is fastened ashore and the hawser is spooled off as the ship moves away from the shore. When the whole of the hawser is spooled off, it is wound up with such force that it lies compact and tight on the drum. This known solution outlined here is consequently a time demanding and costly procedure.

With regard to prior art reference shall be made to the British patent GB 2.311.269 A1. Here, a winch arrangement is described that is intended to control the tension in a steel rope or wire so that it can be spooled tightly from a storage drum to a crane winch, or the like. This solution can be compared with a traditional warping end, with the exception that guides are installed that prevents the steel rope from spinning axially along the drum core when this rotates.

In the U.S. Pat. No. 4,285,502, a disc device controlled by hydraulic cylinders is described, which is intended to hold a steel rope taut, and which can simply release the rope when the device is not to be used. With this embodiment one achieves a pre-tightening of the steel rope with the help of a set of hydraulic cylinders coupled to discs that exert pressure in a sidewise direction against the steel rope. This deviates considerably from the present construction as will become apparent in the following.

It is an aim of the invention to provide a device for a winch system with a drum for coiling of a line (such as a cable, hawser or the like) such that the line is rolled onto the drum with a smoother and stronger tightening.

In particular, it is an aim of the invention to provide a device that can increase the level of tightening on a hawser from a lower tightening level to a higher tightening level.

Thereby, it is also an aim of the invention to provide a solution which can utilise the capacity of the drum in a better way, and that the coiling is smoother than what is normal for today's solutions.

Furthermore, it is a main aim of the invention to provide a construction which is particularly suited to handling of fibrous ropes or fibrous hawsers that shall be coiled, or spooled onto a drum.

It is a further aim of the invention to provide a solution where the surface of the disc groove creates the highest possible friction against the fibrous hawser, at the same time as one shall get the smallest wear damage on the hawser if such gliding occurs.

Thus, one wants to avoid disc grooves with a coating with a coarse or rough surface. If a gliding and subsequent wear do occur, it is less damaging that the contact coating (the rubber disc) is worn than that the hawser is worn.

The device for handling of a line, as described initially, is characterised in that the breaking body comprises brake units that offer a resistance against the coiling of the line on the drum, said breaking body comprises a number of guiding discs for the line, via which the line is set up to be led and form a loop, said guiding grooves of the discs offer said brake effect against the hawser up to the drum.

According to a preferred embodiment, the line is a hawser, such as a fibrous hawser, and the hawser carrying discs, preferably at least two discs, are mutually set up so that the hawser runs in a loop over the discs in the hawser tightening appliance, and preferably there are three discs.

According to a preferred embodiment, said breaking effect is provided in that the guiding grooves of the discs for the hawser are formed with a V or U shape-geometry and comprise a coating (a ring disc form) that provides the highest possible friction between the hawser and the discs.

According to a preferred embodiment, the coating is made from rubber or a rubberised material.

According to a preferred embodiment, one or more of the discs are connected to a motor unit that can create the tightening torque on the discs when the winch is winding up the hawser and the breaking body preferably comprises a hydraulic motor, an electro motor or is formed by a disc-brake or other breaking unit.

According to a preferred embodiment, the guiding body comprises a first guiding wheel to guide the hawser part in a correct path in towards the hawser tightening unit and also a second guiding wheel to guide the taut hawser part from the hawser tightening unit and up to the winch.

According to the invention the device according to the preceding claims for handling of hawsers is used for anchor handling, with the hawsers being loosely wound up on storage drums from the supplier, as the hawser from the storage drum is transferred to a very tightened condition by being wound onto a winch drum (11) with such a force that it lies compact and taut on the drum.

According to the invention the device can according to the preceding claims also be used in the tightening of wires, cables, fibrous hawsers, and the like, on winch drums in connection with cranes.

Consequently, with this invention one has achieved that the hawser can be coiled directly from storage drums and onto the winch of a ship with the correct tightening. This can be carried out as shown in the enclosed figures and the subsequent description.

With the present invention a solution is provided where two or more guiding discs with individual brakes are used. One avoids the problem of axial movement along a drum, as is the case with the construction according to the above mentioned British patent GB 2.311.269. This can cause much damage with the use of synthetic rope as heat is generated from the friction. That the brakes can be adjusted individually is important for the optimisation of the transfer of force from the discs to the rope. The discs form V-shaped guiding grooves and are rubber coated to give a good and gentle transfer of force between the discs and the hawser/rope. To use such appliances onboard an anchor handling vessel in connection with the handling of fibrous ropes has not been practiced previously and will be able to simplify many of today's operations.

The invention shall be explained in more detail in the following, with a hawser being used as a non-limiting example of a line to simplify the explanation of the invention.

In this context, reference is made to the enclosed figures in which:

FIG. 1 shows an example of a preferred embodiment of the device according to the invention.

FIG. 2 shows a detail in the guiding of the hawser through the hawser tightening unit according to the invention.

FIG. 3 shows a side section of a hawser tightening unit with a guiding disc according to the invention.

FIG. 4 shows a side section of the guiding disc.

FIG. 5 illustrates the disc composed of two halves and the coating of a suitable material, such as rubber.

In FIG. 1 a drum in a winch system is shown with the reference number 10 with a drum 11 for winding up of a hawser 12, for example, a slack hawser that is rolled off a storage drum and shall be coiled on a winch. The drum 11 is placed on a foundation 13 and comprises a motor for the winding on and off (not shown) of the hawser 12. Up to the winch 10, the hawser runs as a non-tightened hawser 12 a, according to a preferred embodiment, across a guiding disc 16 that directs it up to a tightening arrangement 20 before it runs on as a hawser stretch 12 b with a higher tightening level in towards the drum 11 where it is coiled. The drum 11 with the motor are fixed constructions on the installation where they are used. The hawser is preferably a fibrous hawser, such as one built up from polyester fibres and/or Kevlar fibres (non-limiting examples).

The guiding pulley 16 comprises an upper 16 a and a lower 16 b guiding wheel that are pulleys which roll freely on a permanent shaft 18. In this example, the incoming, “slack” hawser part 12 a (with a lower tightening level) is led in round the upper guiding pulley 16 a and up to, and through, the hawser tightening unit 20, while the taut hawser part 12 b runs across the lower guiding pulley 16 and on to the winch drum 11. It will appear that the guiding pulleys 16 can be used to guide the direction one wishes the hawser parts 12 a,12 b to have during the tightening and coiling process.

The hawser 12 does not necessarily need to be led into the tightening body via the described guiding pulleys 16 a and 16 b. It can also be led directly into the tightening device 20 i.e., as in the example where the hawser part 12 a (with lower tightening) is led directly into the disc 22 and further out from the disc 21 as the taut hawser part 12 b and directly onto the drum.

The two pulleys 16 a and 16 b shown do not need to be placed across from each other as the figure shows, but can be placed individually at different places in the area.

The Tightening Unit 20 According to the Invention.

The aim is to coil the hawser onto the drum with such tightening that the hawser coils in the spirals from the inner layer outwards shall not bury themselves down between the hawser parts that lies underneath.

According to a preferred embodiment of the invention the hawser tightening unit 20 comprises three discs 21, 22, 23 that rotate in the same plane in the given example. The hawser part 12 a, which initially has a lower tightening level from the disc 16, runs initially

-   -   round a first disc 22,     -   further round a second disc 23, to     -   run into and round a third disc 21         and thereafter further as a hawser part 12 b with a higher         tightening level, via the guiding pulley 16 b and further onto         the drum 10 where it is placed in a tight coil. So that the         discs will get a good grip on/around the hawser, it is important         to have a large degree of encircling on each disc, this means         that as much as possible of the circumference of the guiding         disc comes in direct contact with the hawser. For example, it is         indicated in FIG. 3 that the hawser makes contact with the         groove of the disc 23 via about 270° of the circumference of the         periphery.

The discs 21,22,23 are mutually placed, as shown in FIG. 2, so that the hawser-loop round the discs form said tightened hawser part 12 b in toward the winch. The third disc 23 is placed so that the hawser defines, for example, a U-shaped loop 24 at the exiting hawser from the first disc 21, around the second disc 23 and onto the third disc 22.

The disc groove 30 where the hawser is placed has a V or a U shaped cross section. The V shape is particularly preferred, as the FIGS. 3 to 5 show. The groove surfaces are, preferably covered by a rubber coating (with a ring-disc shape), with a suitable hardness. (a hard rubber type), and which can have a thickness of the order of 1-2 cm, in particular 1 cm, a thickness that can be varied, depending on the dimensions of the hawser and winch system. The coating can be from other suitable materials, such as plastic, as long as they have the above mentioned preferred characteristics with regard to high friction and a smooth surface.

The V-shaped groove surfaces of the discs 21,22,23 are, as shown in FIG. 5, covered by a coating 38 of a material that gives the highest possible friction against the gliding at the same time as it has the smoothest surface possible so that a gentle contact between the natural fibres of the hawser and the surface is made if it should slip in the groove. The coating is preferably from rubber or a rubberised material with a suitable hardness, and particularly with a relatively smooth surface structure with minimum roughness. As it appears in FIG. 4, the surfaces of the disc groove form an angle α with each other, and in a typical case an angle of 60°.

One or more of the discs 21,22,23 can comprise a breaking body 40 or a hawser tightening unit, as shown in FIG. 4, and which can provide a tightening creating moment on the discs when the winch 10 works and coils the hawser. The breaking body can comprise a hydraulic motor, an electro motor, or is made from a disc brake or other brake unit. The hawser tightening unit 40 preferably comprises a motor 36 with a gear 34, and which can be operated as a breaking body. In addition, the motor 36 can be driven so that the unit 20 can be used to pull in a hawser 12. In the present case, all the three discs 21,22,23 can be connected to their own motor unit 40.

An example is shown where the hawser 12 b is placed in the pulley groove 30 of the disc 21. The pulley is fitted in a shaft (not shown) that is driven by the motor 36.

As FIG. 5 illustrates, the disc 21 is composed of two disc halves and the groove forming surfaces are coated with a suitable material, such as rubber. In FIG. 3, a fitting bracket with reference number 32 is indicated, that is used for the fitting of the tightening unit 40 in connection with a deck construction, for example, so that the gear 34 and motor 36 are placed below the deck of the vessel with only the disc lying above the deck level where the hawsers are handled. The construction can, of course, be placed anywhere and in any desirable position. The construction according to the invention with the motor-driven guiding discs can also be driven to pull hawsers across the discs, for example, when the hawser shall be pulled off the drum 11.

The following characteristics of the present described construction are given, with regard to prior art, for example, as shown in the two above mentioned patents:

-   1) The solution is directed towards application of fibrous hawsers     and not wires. -   2) The disc groove is V-shaped and has a friction coating in the     form of a rubber coating. -   3) With the solution, individual breaking of the guiding discs     21,22,23 is used. -   4) With the use of such guiding discs, one avoids any axial movement     of the hawser as in, for example, the GB patent. -   5) A great extent of surface contact, i.e. the hawser lies against     the disc groove for most of its circumference. -   6) One obtains a solution that offers low wear of the fibrous hawser     if slipping occurs in the disc groove. 

1.-8. (canceled)
 9. A method for coiling a slack hawser onto a winch drum comprising the steps of providing a storage drum with a hawser coiled thereon; providing a winding drum for coiling of the hawser from said storage drum thereon; running the hawser in a slack condition from the storage drum to and about at least one guiding wheel located between said storage drum and said winding drum; and conducting the hawser from the guiding wheel to and through a braking body including a plurality of hawser guiding discs, each of said discs having a guiding groove with frictional surfaces for frictionally guiding the hawser thereon, at least one of said discs including braking means for imparting a tightening creating moment on the discs to tighten the hawser conducted therearound and extending to said winding drum; and running the hawser from said braking body to said winding drum with a tension sufficient to coil the hawser on said winding drum in successive layers without a hawser part in an outer layer of said layers sinking down between hawser parts in an underlying layer of said layers.
 10. A method according to claim 9 wherein said discs are disposed relative to each other to conduct the hawser thereover with the hawser frictionally contacting about 270° of the circumferential surface of the guiding groove of each respective disc.
 11. A method according to claim 10 wherein said discs number three.
 12. A method according to claim 10 wherein each frictional surface of each respective disc has a coating of rubber thereon for contacting the hawser.
 13. A method according to claim 10 wherein the guiding groove of each respective disc has a V-shape.
 14. A method according to claim 9 further comprising the step of conducting the hawser from the braking body over a second guiding wheel to said winding drum.
 15. An apparatus comprising a winding drum for coiling of a hawser from a storage drum thereon; at least one guiding wheel for conducting a hawser from the storage drum therearound in a slack condition; and a braking body including a plurality of hawser guiding discs for receiving the hawser from said guiding wheel in a slack condition and conducting the hawser to said winding drum in a taut condition, each of said discs having a guiding groove with frictional surfaces for frictionally guiding the hawser thereon, at least one of said discs including braking means for imparting a tightening creating moment on said discs to tighten the hawser conducted therearound and extending to said winding drum whereby to coil the hawser on said winding drum in successive layers without a hawser part in an outer layer of said layers sinking down between hawser parts in an underlying layer of said layers.
 16. An apparatus according to claim 14 wherein said discs number three and are disposed relative to each other to conduct the hawser thereover with the hawser frictionally contacting about 270° of the circumferential surface of the guiding groove of each respective disc.
 17. An apparatus according to claim 14 wherein each frictional surface of each respective disc has a coating of rubber thereon for contacting the hawser and said guiding groove of each respective disc has a V-shape.
 18. An apparatus according to claim 14 wherein said brake body includes a motor for rotating at least one of said guiding wheel and said discs.
 19. An apparatus according to claim 14 further comprising a second guiding wheel for conducting the hawser in said taut condition from said braking body to said winding drum. 